DOA Estimation of Multiple LFM Sources Using a STFT-based and FBSS-based MUSIC Algorithm

Abstract

Abstract. Direction of arrival (DOA) estimation is an important problem in array signal processing. An effective multiple signal classification (MUSIC) method based on the short-time Fourier transform (STFT) and forward/ backward spatial smoothing (FBSS) techniques for the DOA estimation problem of multiple time-frequency (t-f) joint LFM sources is addressed. Previous work in the area e. g. STFT-MUSIC algorithm cannot resolve the t-f completely or largely joint sources because they can only select the single-source t-f points. The proposed method constructs the spatial t-f distributions (STFDs) by selecting the multiple-source t-f points and uses the FBSS techniques to solve the problem of rank loss. In this way, the STFT-FBSS-MUSIC algorithm can resolve the t-f largely joint or

DOA Estimation of LFM Signal Based on Single-Source Time-Frequency Points Selection Algorithm by Using the Hough Transform

“…1. Figure 1(b) represents that signals are largely overlapped in TF domain, and the reference [19] has proposed efficient DOA estimation method. Therefore, we mainly study that signals are tiny non-disjoint in TF domain, which means that there always exist most TF points that are only associated with this signal, as is shown in Fig.…”

“…In order to analyze the angular resolution and DOA estimation accuracy of the proposed algorithm, the comparison between the proposed algorithm, the TF-MUSIC algorithm [8] and the TF-FBSS-MUSIC algorithm [19] are presented in Fig. 7 and Fig.…”

“…In order to verify the effectiveness of the proposed method, we carry out the experiment in the standard micro- wave anechoic chamber. It should be noted that the reference [19] has constructed the hardware experimental platform, and we use the same platform to verify the proposed algorithm. The sketch map of the platform is shown in Fig.…”

“…However, due to the contradiction between time resolution and frequency resolution, the description accuracy of STFT is low in TF domain, which results in poor DOA estimation performance. In addition, the reference [19] used the forward-backward spatial smoothing (FBSS) algorithm to eliminate the influence of multiplesource TF points in TF domain. Although the algorithm can estimate the DOAs of LFM signals, the estimation accuracy is low owing to the spatial smoothing process.…”

“…The auto-term TF points contain single-source TF points and multiple-source TF points. According to [19], by carrying singular value decomposition (SVD) of the STFD matrix, we can obtain the signal subspace matrix. The matrix is column full-rank at the single-source TF points and the rank is equal to the number of signals.…”